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Physical and chemical characterization of sediments from an Andean river exposed to mining and agricultural activities: The Moquegua River, Peru

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International Journal of Sediment Research 2022年第6期37卷 780-793页

作者： luis de Los Santos Valladares juan luis ccamapaza Renato Arturo Valencia-Bedregal luis Enrique Borja-Castro Jose Velazquez-Garcia Dehiwalage Harshani Nimalika Perera Adrian Ionescu David Arvidsson Eustace Peregrine Barnes Peter Newton Hugo Lepage Patrick Byrne Angel Guillermo Bustamante Dominguez Crispin H.W.Barnes Cavendish Laboratory Department of Physics University of Cambridge Escuela Acad emico Profesional de Ingeniería Ambiental Universidad Nacional de Moquegua Provincia de Mariscal Nieto Laboratorio de Cer amicos y Nanomateriales Facultad de Ciencias Físicas Universidad Nacional Mayor de San Marcos School of Biological and Environmental Science Liverpool John Moores University

This study presents an analysis of sediments in an Andean river impacted by both natural conditions and anthropogenic activities. Fifty samples were collected from selected sites throughout the Moquegua River drainage basin, and Tambo River headwaters at Pasto Grande, in Peru, and analysed with X-ray diffraction, energy dispersive X-ray spectroscopy, scanning electron microscopy, Fourier-transform infrared spectroscopy and thermogravimetric analysis. Si, Ca, Al, Fe, and O, common constituents of soils, were dominant, along with K, N, and P. The latter originating as primary macronutrients or chemical residuals from fertilizers used in agriculture. Higher concentrations of macronutrients and organic components were found in agricultural and urban areas, respectively. Arsenic minerals were also detected, which occur naturally, but possibly at levels augmented by anthropogenic activity. The application of cluster analysis revealed clustering between arsenic, arsenolite, and potassium but no significant geospatial correlation between sample sites in the drainage basin.

关键词： Andean river Moquegua river Sediments Fourier-transform infrared spectroscopy TG-DTG/DTA Clustering analysis

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Performance assessment of two-dimensional hydraulic models for generation of flood inundation maps in mountain river basins

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Water Science and Engineering 2019年第1期12卷 11-18页

作者： juan Pinos luis Timbe Department of Water Resources and Environmental Sciences University of Cuenca

Hydraulic models for the generation of flood inundation maps are not commonly applied in mountain river basins because of the difficulty in modeling the hydraulic behavior and the complex topography. This paper presents a comparative analysis of the performance of four twodimensional hydraulic models (HEC-RAS 2D, Iber 2D, Flood Modeller 2D, and PCSWMM 2D) with respect to the generation of flood inundation maps. The study area covers a 5-km reach of the Santa B-arbara River located in the Ecuadorian Andes, at 2330 masl, in Gualaceo. The model's performance was evaluated based on the water surface elevation and flood extent, in terms of the mean absolute difference and measure of fit. The analysis revealed that, for a given case, Iber 2D has the best performance in simulating the water level and inundation for flood events with 20- and 50-year return periods, respectively, followed by Flood Modeller 2D, HEC-RAS 2D, and PCSWMM 2D in terms of their performance. Grid resolution, the way in which hydraulic structures are mimicked, the model code, and the default value of the parameters are considered the main sources of prediction uncertainty.

关键词： Two-dimensional hydraulic models Flood modeling Flood extent Water surface elevation High mountain river Ecuador

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Pathogenesis and clinical management of arboviral diseases

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World Journal of Virology 2025年第1期14卷 9-50页

作者： Victoria Cenci Dietrich juan Marcos Caram Costa Marina Maria Gomes Leite Oliveira Carlos Eduardo Oliveira Aguiar luis Guilherme de Oliveira Silva Marcel Silva Luz Fabian Fellipe Bueno Lemos Fabrício Freire de Melo Instituto Multidisciplinar em Saúde Universidade Federal da BahiaVitória da Conquista 45029-094BahiaBrazil

Arboviral diseases are viral infections transmitted to humans through the bites of arthropods,such as mosquitoes,often causing a variety of pathologies associated with high levels of morbidity and *** the past decades,these infections have proven to be a significant challenge to health systems worldwide,particularly following the considerable geographic expansion of the dengue virus(DENV)and its most recent outbreak in Latin America as well as the difficult-tocontrol outbreaks of yellow fever virus(YFV),chikungunya virus(CHIKV),and Zika virus(ZIKV),leaving behind a substantial portion of the population with complications related to these ***,the world is experiencing a period of intense globalization,which,combined with global warming,directly contributes to wider dissemination of arbovirus vectors across the ***,all continents remain on high alert for potential new ***,this review aims to provide a comprehensive understanding of the pathogenesis of the four main arboviruses today(DENV,ZIKV,YFV,and CHIKV)discussing their viral characteristics,immune responses,and mechanisms of viral evasion,as well as important clinical aspects for patient *** includes associated symptoms,laboratory tests,treatments,existing or developing vaccines and the main associated complications,thus integrating a broad historical,scientific and clinical approach.

关键词： Arboviruses Arbovirus infections Dengue Zika virus Yellow fever Chikungunya virus Clinical diagnosis Pathogenesis Flavivirus Togaviridae infections

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Symmetrization for Fractional Elliptic and Parabolic Equations and an Isoperimetric Application(Dedicated to Haim Brezis,great master of analysis,on his 70th birthday)

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Chinese Annals of Mathematics,Series B 2017年第2期38卷 661-686页

作者： Yannick SIRE juan luis VAZQUEZ Bruno VOLZONE johns hopkins university Krieger Hall3401 N.Charles StBaltimoreM D21218USA. departamento de matemticas universidad autnoma de madrid28049 M adridSpain dipartimento di ingegneria universit degli studi di napoli"parthenope"80143 Italia.

This paper develops further the theory of symmetrization of fractional Laplacian operators contained in recent works of two of the authors. This theory leads to optimal estimates in the form of concentration comparison inequalities for both elliptic and parabolic equations. The authors extend the theory for the so-called restricted fractional Laplacian defined on a bounded domain Ω of R^N with zero Dirichlet conditions outside of Ω. As an application, an original proof of the corresponding fractional Faber-Krahn inequality is derived. A more classical variational proof of the inequality is also provided.

关键词： Symmetrization, Fractional Laplacian, Nonlocal elliptic and parabolicequations, Faber-Krahn inequality

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Experimental analysis of infragravity waves in two eroded microtidal beaches

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Acta Oceanologica Sinica 2017年第5期36卷 31-43页

作者： MARIO Conde-Frias luis Otero juan Camilo Restrepo juan Carlos Ortiz Geosciences Research Group GE04 Department of PhysicsUniversidad del NorteBarranquilla 081007Colombia

This work aims to contribute to the characterization and understanding ofinfragravity waves on two beaches with erosion problems. For this reason, we have used an array of ADCP and a pressure sensor to measure wave parameters and pressure inside and outside of the surf zone during the dry and rainy period in the beaches of Galerazamba and Manzanillo del Mar （both dissipative and eroded beaches） located in the Colombian Caribbean coast. Based on these measurements, we have carried out a spectral analysis in order to identify the frequency components that characterize the wave and its energy; thus, we identified the characteristic frequencies of iufragravity waves to finally filter the infragravity signal on each beach in different seasonal periods. Among the results of the Welch spectrum applied to surface elevation time series, we found that, the frequencies＇ energy of the sea-swell band decreases due to bottom friction and wave breaking as the wave approaches the shore, while the frequencies＇ energy of the infragravity band increases significantly. In addition, for the wavelet analysis, we could observe how the energy of the infragravity band, especially the lowest frequencies gain energy as the waves approaches the coast. Furthermore, based on the infragravity wave obtained from the extreme wave event registered during the field campaign we can conclude that the contribution of this signal is important in the erosion problems presented in the beaches of Galerazamba and Manzanillo del Mar. Finally, these results show the need to realize other studies that allow us to understand deeply, the role of infragravity waves on the morphological changes that occurs in these beaches.

关键词： infragravity waves long waves experimental analysis fourier analysis wavelet transform

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Mycobacterium avium subspecies paratuberculosis and its relationship with Crohn's disease

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World Journal of Gastroenterology 2009年第4期15卷 417-422页

作者： juan luis Mendoza Raquel Lana Manuel Díaz-Rubio Inflammatory Bowel Disease Unit Department of GastroenterologyHospital Clínico San CarlosUniversidad Complutense Department of Internal Medicine Hospital Clínico San CarlosUniversidad Complutense

The hypothesis postulating that Mycobacterium avium paratuberculosis(MAP) is the cause of Crohn's disease(CD) has been circulating for many *** in molecular techniques,such as polymerase chain reaction and culture methods,have enabled researchers to demonstrate that there is an association between MAP and ***,genome-wide association studies have identified novel susceptibility genes for CD,which are critical for generation of an adaptive immune response that is protective against intracellular pathogens,including *** ***,the role of MAP as a cause of CD suffered a setback with the report that administration of antimycobacterial therapy failed to lead to a sustained response in CD ***,this review sought neither to confirm nor refute this,but instead to survey recent literature on the role of MAP in CD.

关键词： Mycobacterium avium subspecies paratuber-culosis Crohn's diasease Inflammatory bowel disease

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The political economy of city diplomacy

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Economic and Political Studies 2022年第2期10卷 228-249页

作者： juan luis Manfredi-Sanchez Department of International Studies&Journalism University of Castilla-La ManchaToledoSpain

City diplomacy is a major trend in the soft power *** cities face daily political issues deriving from globalisation(such as mass tourism,migration,climate change,and commodifi-cation of culture),they demand for,rather than contesting with a nationstate,an operational reinterpretation of sovereignty ori-ented to solve *** economy approach is a useful method to understand the role of global cities where the nation state has many *** global city establishes rules to influence international legal development and practice,even with-out a traditional legal basis(such as sovereignty,monopoly on violence,and legal exclusivity).As these‘superstar cities’grow,other cities are losing opportunities to develop and take advan-tage of *** risk of inter-urban inequality feeds *** will become the middle power in global political organisations in the future,and political economy will shed light on how power and values operate at the urban level.

关键词： City diplomacy leadership political economy sanctuary city urban agenda

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Does an association exist between chronic pancreatitis and liver cirrhosis in alcoholic subjects?

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World Journal of Gastroenterology 2008年第40期14卷 6171-6179页

作者： luis Aparisi luis Sabater juan Del-Olmo juan Sastre Miguel-Angel Serra Ricardo Campello Daniel Bautista Abdalla Wassel José-Manuel Rodrigo Liver Unit Universitary Clinic Hospital Department of Surgery Universitary Clinic Hospital Department of Physiology University of Valencia Unit of Psiquiatry Servicio Valenciano de SaludValencia 46010Spain Department of Preventive Medicine Hospital Dr.Peset

AIM: To study the possible association between chronic pancreatitis (CP) and liver cirrhosis (LC) of alcoholic etiology,after excluding any other ***: One hundred and forty consecutive alcoholic patients were subdivided into three groups: CP (n = 53),LC (n = 57),and asymptomatic alcoholic (n = 30).Clinical,biochemical and morphological characteristics,Child-Pugh index,indocyanine green test,and fecal pancreatic elastase-1 test were ***: In patients with cirrhosis,major clinical manifestations of CP such as pancreatic pain and steatorrhea,as well as imaging alterations of CP such as calcifications,duct dilation and pseudocysts were absent; insulin-dependent diabetes was present in 5.3% of cases,and elastase-1 test was altered in only 7%,and severely altered in *** patients with CP,clinical characteristics of cirrhosis such as ascites,encephalopathy and gastrointestinal hemorrhage were present in one case,Child-Pugh grade > A in 5.7%,and altered indocyanine green test in 1.9% *** asymptomatic alcoholism,there was only a non-coincident alteration of elastase-1 test and indocyanine test in 14.8% and 10%,respectively,but other characteristics of cirrhosis or CP were *** inverse correlation (r = -0.746) between elastase-1 test and indocyanine test was found in alcoholic ***: There is a scarce coincidence in clinical and morphological alterations among patients with CP or LC of alcoholic etiology,but an inverse correlation between pancreatic and liver function *** findings support that these alcoholic diseases evolve in a different manner and have different etiopathogenesis.

关键词： Alcoholic chronic pancreatitis Alcoholicliver cirrhosis Alcoholism Pancreatic function Hepaticfunction

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Malignant colorectal polyps

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World Journal of Gastroenterology 2010年第25期16卷 3103-3111页

作者： luis Bujanda Angel Cosme Ines Gil juan I Arenas-Mirave Department of Gastroenterology Donostia Hospital Uni-versity of Basque Country Centro de Investigación Biomédica en Enfermedades Hepáticas y Digestivas 20010 San Sebastián Guipúzcoa Spain University of Basque Country Centro de Investigación Biomédica en Enfermedades Hepáticas y Digestivas 20010 San Sebastián Guipúzcoa Spain

Nowadays, the number of cases in which malignant colorectal polyps are removed is increasing due to colorectal cancer screening programmes. Cancerous polyps are classified into non-invasive high grade neoplasia (NHGN), when the cancer has not reached the muscularis mucosa, and malignant polyps, classed as T1, when they have invaded the submucosa. NHGN is considered cured with polypectomy, while the prognosis for malignant polyps depends on various morphological and histological factors. The prognostic factors include, sessile or pedunculated morphology of the polyp, whether partial or en bloc resection is carried out, the degree of differentiation of the carcinoma, vascular or lymphatic involvement, and whether the polypectomy resection margin is tumor free. A malignant polyp at T1 is considered cured with polypectomy ifit is a pedunculated polyp (Ip of the Paris classification), it has been completely resected, it is not poorly differentiated, the resection edge is not affected by the tumor and there is no vascular or lymphatic involvement. The sessile malignant polyp (Is of the Paris classification) at T1 is considered not cured with polypectomy. Only in some cases (e.g. older people with high surgical risk) local excision(polypectomy or endoscopic submucosal dissection or conventional endoscopic mucosal resection) is considered the definitive treatment.

关键词： Favourable histology Follow-up Malignant polyps Non-invasive high grade neoplasia Treatment

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Suspended sediment transport in the Magdalena River(Colombia,South America):Hydrologic regime,rating parameters and effective discharge variability

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International Journal of Sediment Research 2016年第1期31卷 25-35页

作者： Aldemar Higgins juan Camilo Restrepo juan Carlos Ortiz Jorge Pierini luis Otero (UNS-CIC-CCT)

The Magdalena River has the greatest length（1612 km）and drainage area（257400 km2）of any river system in Colombia,and its watershed occupies 24%of the Colombian *** river originates in the Andean Cordillera at an elevation of 3685 m and flows to its mouth in the Caribbean Sea（Bocas de Cenizas）.For this study,information on daily flow discharge（Q）,suspended sediment transport(Qsand mean suspended sediment concentration（Cs）from 1990-2010 for the Magdalena River,based on measurements at the Caiamar gauging station（the closest station to the mouth）,was provided by the Institute of Hydrology,Meteorology and Environmental Studies of Colombia（IDEAM in Spanish）.The mean annual suspended sediment load was 169±73×10～6tyr-1for the period from 1990-1999 and145±47×10～6 t yr1for the period from 2000-2010,amounting to a 14%reduction in the suspended sediment transport rate between the two *** sediment rating curve（Qs=aQb）was also evaluated for these two periods（1990-1999 and 2000-2010）.An analysis of the regression coefficients（a.b）for the two periods showed a decrease in b and an increase in a after 1999,which coincides with a decrease in suspended sediment *** change might be attributed to natural factors,including the accumulation of sediment in the Depresion Momposina and variation in hydro-climatological patterns in the Caribbean *** in effective transport were confirmed using three methods（Log-Normal and Normal distribution,and magnitude-frequency histogram）for the study period.

关键词： Suspended sediment transport Magdalena River Transport regime Effective discharge Sediment rating curve

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